1. Technical Field
The present invention relates to a camera module.
2. Description of the Related Art
Recently, as a high-resolution, multi-functional, and micro camera module is widely spread, the use of the camera module has been more expanded for mobile devices, such as a mobile phone, a notebook PC, a tablet PC, and the like.
In addition, as the camera module is miniaturized, it is more difficult to manufacture and assemble an optical system that includes a lens that is a core component configuring a camera device, an auto-focusing (AF) device that controls a focus by moving the optical system to an optical axis, an image sensor (CMOS, CCD sensor, and the like) that changes a subject to an electrical signal, and the like. There is a problem in that the performance of the camera module that is smaller and smaller so as to apply each component and a design between components, a level of manufacturing tolerance and assembling tolerance, and the like, that slightly affect performance in a camera of the existing digital camera level or more to mobile devices is degraded, such that it is more difficult to obtain a high-quality image.
In more detail, a user's handshake occurs at the time of photographing and image blurring occurs due to the handshake, such that a clear image cannot be obtained. That is, when a user intends to photograph a subject by starting a camera operation, the lens moves in an optical axis direction in the case of the camera including the auto-focusing function to clearly focus an image of a subject on an imaging device (image sensor).
When the auto-focusing function is performed, the clear image can be generally obtained, but the image blurs due to the user's handshake at the time of photographing without using a fixation, such as a tripod, and the like. When the handshake does not occur, the subject image is focused on the imaging device as an optimal focus. In this case, when the handshake occurs by the user, the image blurring occurs. In this case, the image blurring is prevented by focusing the same image at the same position at all times in terms of the image sensor by moving the optical lens in a direction vertical to the optical axis, such that the clear image can be obtained.
As described above, a method for compensating for the handshake by moving the lens in the direction vertical to the optical axis is generally referred to as a lens moving method. On the other hand, a method for fixing the lens and moving the image sensor in a direction vertical to the optical axis is referred to as a sensor moving method. As a result, the handshake is compensated by giving the relative displacement of the lens and the image sensor in the direction vertical to the optical axis.
However, the camera module such as Patent Document described in the following Prior Art Document further includes a handshake compensating device in addition to the auto-focusing device.
In this case, the handshake compensating device generally needs a two-axis actuator, such that the assembling man-hour is increased while increasing the number of components of the camera module. In addition, the handshake compensating device also affects the size of the camera module, such that the size of the camera module may generally be increased.